"In the two decades after 1950, the crude death rate of the Chinese population was reduced by nearly 60 percent, from 18 per thousand in 1950 to 7.6 in 1970."

Life Expectancy

[in 50 years/ 1950-2000] China accomplished what it took these other countries [more developed european countries and US] a century to achieve, an increase in life expectancy from the 40s to over 70 years.

Fertility

"In contrast to western european countries, where it took 75 years or longer to complete a fertility transitionfrom a TFR of around 5 to the replacement level, in China a similar decline took only about two decades."

Demographic Transition

"In roughly half a century, China completed its transition from a low rate of natural increase due to high mortality and high fertility to a low rate of natural increase as a result of low mortality and low fertility."

Family

"Moreover, the large number of families with only one child, often against the will of the parents, presents serious economic and social risks for Chinese families and for society as a whole."

Labor Force and Aging

"China’s economic boom has relied on another crucial factor, namely a young and productive labor force. This large labor force, a non-repeatable historical product of the rapid demographic transition, was present fortuitously as the Chinese economy was about to take off."

"China’s rapidly shrinking young labor force, a result of very low fertility for nearly two decades, will soon end the era of abundant supply of inexpensive labor that enabled China to become the world’s largest manufacturing center in the last two decades."

My take: China is perhaps one of the few countries that have completed its fertility transition without completing its urban transition. It means that China still has large amount of rural-urban migration potential, which could keep an abundant supply of inexpensive labor for many decades. Perhaps this potential is being underestimated.